Our reflections on IPC based on clinical microbiology, epidemiology, science & literature, and the practical issues that we run into day to day

staphylococcus aureus

Have you ever wondered how on earth vegetative bacteria can survive on dry surfaces for years? Or why when you have an outbreak and you swab the environment you don’t find the outbreak strain even though you’re pretty sure it’s there? Or why a disinfectant that gets a 4-log reduction in the lab can’t eliminate a couple of hundred cfu of bacteria from a dry surface? Dry surface biofilms could be the answer to all these questions! I was involved in a multicentre survey of dry biofilms from across the UK, and we identified dry surface biofilms on 95% of the 61 samples there were tested. Worryingly, viable MRSA was identified on 58% of the surfaces! We need to think carefully about how much of a risk dry surface biofilms present, and whether we need to do more to tackle them.